CN105405959B - A kind of ternary system relaxation ferroelectric single crystal piezoelectric transformer of transversal stretching vibration mode - Google Patents

A kind of ternary system relaxation ferroelectric single crystal piezoelectric transformer of transversal stretching vibration mode Download PDF

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CN105405959B
CN105405959B CN201510725277.5A CN201510725277A CN105405959B CN 105405959 B CN105405959 B CN 105405959B CN 201510725277 A CN201510725277 A CN 201510725277A CN 105405959 B CN105405959 B CN 105405959B
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lead
piezoelectric transformer
single crystal
ternary system
ferroelectric single
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CN105405959A (en
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王飞飞
石旺舟
罗豪甦
马传国
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Shanghai Normal University
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    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N30/00—Piezoelectric or electrostrictive devices
    • H10N30/40—Piezoelectric or electrostrictive devices with electrical input and electrical output, e.g. functioning as transformers
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N30/00—Piezoelectric or electrostrictive devices
    • H10N30/80—Constructional details
    • H10N30/85—Piezoelectric or electrostrictive active materials
    • H10N30/853—Ceramic compositions
    • H10N30/8536—Alkaline earth metal based oxides, e.g. barium titanates
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N30/00—Piezoelectric or electrostrictive devices
    • H10N30/80—Constructional details
    • H10N30/85—Piezoelectric or electrostrictive active materials
    • H10N30/853—Ceramic compositions
    • H10N30/8548—Lead based oxides

Abstract

The invention provides a kind of ternary system relaxation ferroelectric single crystal piezoelectric transformer of transversal stretching vibration mode, the monocrystalline piezoelectric transformer includes piezoelectric element, and the piezoelectric element material is lead magnesio-niobate lead niobate lead indate-lead lead titanate monocrystal.Ternary system relaxation ferroelectric single crystal piezoelectric transformer small volume provided by the invention, light weight, make it is simple, the power density of current piezoelectric transformer can be significantly improved, meet the miniaturization of relevant information processing equipment and integrated requirement, be a kind of power device simple in construction, high comprehensive performance.

Description

A kind of ternary system relaxation ferroelectric single crystal piezoelectric transformer of transversal stretching vibration mode
Technical field
The invention belongs to electricity field, is related to a kind of transformer, more particularly to a kind of ternary of transversal stretching vibration mode It is relaxor ferroelectric monocrystal piezoelectric transformer.
Background technology
With being miniaturized of information processing apparatus, integrated there is an urgent need to be reached its maturity with drive circuit, become Depressor is extended to AC/DC, DC/DC conversion constant power field of electronic devices, these work(from high pressure field (power is generally smaller) Rate electronic device is required to realize larger power output in smaller size smaller, prepares the new transformation with high power density Device also turns into the focus of Recent study.
Piezoelectric transformer is that one kind is based on piezoelectricity coupling effect, is become by impedance and brings the electronics member device for realizing voltage up-down Part.Compared with traditional electromagnetic transformers, there is big transformation ratio, high conversion efficiency, protected without electromagnetic interference, high temperature resistant and short circuit The advantages of shield etc. is unique.
Piezoelectric is the core parts of piezoelectric transformer, and the quality of piezoelectric performance directly determines transformer performance Quality, the mainly piezoelectric ceramics that traditional piezoelectric transformer uses, further to reduce its volume, hoisting power density, There is an urgent need to find new High-power piezoelectric material.
With PMN-PT ((1-x) Pb (Mg1/3Nb2/3)O3-xPbTiO3) (hereinafter abbreviated as PMN-PT) be representative Binary series high-performance relaxor ferroelectric monocrystal material near quasi- homotype phase boundary tripartite's alpha region piezoelectric property up to piezoelectric ceramics 5-10 times of material, wherein, piezoelectric coefficient d33And d312,500pC/N, 2, more than 000pC/N, mechanical-electric coupling can be reached respectively Coefficient k33And k31More than 90% can be reached, therefore, shown in the application of transducer of new generation, driver and sensor Go out extraordinary prospect, also result in the extensive concern of scientific and technological circle and industrial quarters.
Applicant utilizes the excellent piezoelectric property of PMN-PT monocrystalline, takes the lead in reporting individual layer and multilayer Rosen type transformers, Wherein individual layer Rosen types transformer open circuit step-up ratio reaches 138, and power density is about 4 times of pattern ceramic transformer of the same race, turns Efficiency is changed up to 95%.
However, further study show that, binary system PMN-PT monocrystalline has that coercive field is relatively low, moves back pole in high-power applications Change the problem of temperature is not high enough, i.e., the problem of making material property degradation in the presence of heating, and then cause component failure, this is for transformation Application of the device under relatively high power is very unfavorable.How the same of high tension electricity coefficient and electromechanical coupling factor is being kept When, mechanical quality factor is improved, loss is reduced, increases the coercive field of monocrystalline and widen temperature use range and just seem very heavy Will.
Research shows, on the basis of binary system PMN-PT monocrystalline, introduces indium (In) element and prepares ternary system relaxor ferroelectric Monocrystalline PMN-PIN-PT, can make monocrystalline coercive field increase to more than 5kV/cm from 2-3kV/cm, and depolarization temperature is improved to 100 DEG C More than, the mechanical quality factor of monocrystalline has also increased, and ternary system relaxation ferroelectric single crystal PMN-PIN-PT is on sonac Have begun to use, but do not find its relevant report on the transformer so far.
The content of the invention
In order to solve above mentioned problem existing for binary system PMN-PT monocrystalline piezoelectric transformers, the present invention provides one kind and laterally stretched The ternary system relaxation ferroelectric single crystal piezoelectric transformer of contracting vibration mode.
It is an object of the invention to provide a kind of ternary system relaxation ferroelectric single crystal piezoelectricity transformation of transversal stretching vibration mode Device, the monocrystalline piezoelectric transformer include piezoelectric element, and the material of the piezoelectric element is lead magnesio-niobate-lead niobate lead indate-lead-metatitanic acid Lead (PMN-PIN-PT) monocrystalline.
As a preferred embodiment of the present invention, the PMN is lead magnesio-niobate, and the PIN is lead niobate lead indate-lead, the PT For lead titanates.
As a preferred embodiment of the present invention, the chemical composition of the PMN-PIN-PT is (1-x-y) Pb (Mg1/ 3Nb2/3)O3–yPb(In1/2Nb1/2)O3-xPbTiO3, wherein, x=0.05-0.50, y=0.05-0.50；Preferably x=0.25- 0.35, y=0.30-0.38.
As a preferred embodiment of the present invention, the PMN-PIN-PT is located at quasi- homotype phase boundary tripartite's phase region nearby Domain.
As a preferred embodiment of the present invention, the crystallographic orientation of the PMN-PIN-PT is square along [100] for length To, thickness edge [011] direction, width edgeDirection.
As a preferred embodiment of the present invention, the piezoelectric element includes upper and lower surface, the upper surface Including importation and output par, c, the importation includes at least two input, and the output par, c includes at least one Output end, the output end is between the input；The lower surface includes common ground end.
As a preferred embodiment of the present invention, the common ground end is full electrode.
As a preferred embodiment of the present invention, it can be connected in parallel or be connected in series between the input, and it is excellent Elect as and be connected in parallel.
As a preferred embodiment of the present invention, in the upper surface fired electrodes of the piezoelectric element, the electrode will The piezoelectric element is divided at least three identical parts, respectively as the input and output end of transformer, respectively from institute State upper/lower electrode of the upper and lower surface lead of input and the output end as the monocrystalline piezoelectric transformer.
As a preferred embodiment of the present invention, the ferroelectric single crystal material PMN-PIN-PT is along thickness [011] direction Polarization, polarised direction is from upper surface to lower surface.
As a preferred embodiment of the present invention, the ferro-electricity single crystal size is：Length：Width >=5：1st, width：It is thick Degree >=3：1.
As a preferred embodiment of the present invention, the ferro-electricity single crystal size is length (12-25) mm ╳ width (1-6) Mm ╳ thickness (0.5-3) mm, preferably length (15-18) mm ╳ width (2-4) mm ╳ thickness (0.5-2) mm.
As a preferred embodiment of the present invention, the Top electrode size shape of the input, output end is just as, size It is equal.
As a preferred embodiment of the present invention, the Top electrode size of the input, output end is：Length 4-7mm, Width 1-6mm；Preferably length 5-6mm, width 2-4mm.
As a preferred embodiment of the present invention, the direction of vibration of the input and output end is along its length.
As a preferred embodiment of the present invention, the input is identical with output end shape, equal sized.
As a preferred embodiment of the present invention, 0.5-2mm, such as 0.7mm are spaced between the input and output end, 1.8mm；Preferably 0.8-1.5mm, such as 1.0mm.
As a preferred embodiment of the present invention, the monocrystalline piezoelectric transformer using one kind in silver, gold, platinum etc. or Several compositions are preferably used as electrode, more preferably using the silver fired as electrode as electrode using silver.
The present invention using the high-curie temperature of ternary system piezoelectric monocrystalline, high phase transition temperature, big coercive field, high tension electricity coefficient and The properties such as superior mechanical-electric coupling performance obtain high power density output, up to 50W/cm3More than, about current phase 6 times of the power density of same type piezoelectric ceramic transformer.The device volume is small, light weight, makes simple, can significantly improve The power density of current piezoelectric transformer, meet the miniaturization of relevant information processing equipment and integrated requirement, be a kind of structure Simply, the power device of high comprehensive performance.
Brief description of the drawings
Fig. 1 is the structural representation of monocrystalline piezoelectric transformer provided by the invention；
Fig. 2 is the impedance spectra near monocrystalline piezoelectric transformer inputs resonant frequency provided by the invention；
Fig. 3 is the impedance spectra near monocrystalline piezoelectric transformer output end resonant frequency provided by the invention；
Fig. 4 is monocrystalline piezoelectric step-up ratio provided by the invention with different loads and the change curve of frequency；
Fig. 5 is that power output and the relation of input voltage are bent under monocrystalline piezoelectric transformer matched load provided by the invention Line.
Embodiment
Monocrystalline piezoelectric transformer device structure
As shown in figure 1, being ternary system relaxation ferroelectric single crystal piezoelectric transformer provided by the invention, it is length 17mm to take size ╳ width 3mm ╳ thickness 1mm monocrystalline, silver electrode is fired in monocrystalline upper surface, monocrystalline is divided into identical size by silver electrode Three parts, three parts are respectively as the input and output end of transformer, and output end is between input.Respectively from input With the upper/lower electrode of the upper and lower surface lead of output end as transformer, two inputs are connected in parallel.
Transformer includes importation and output par, c, and importation includes two inputs in left and right, and output par, c is located at Between two inputs, the upper surface interval 1mm of importation and output par, c, importation shares bottom surface with output par, c, As the common ground end of transformer, i.e., importation, the upper surface size of output par, c are length 5mm, width 3mm.
Ternary system relaxation ferroelectric single crystal piezoelectric transformer provided by the invention using the silver fired as electrode, silver electrode Thickness is 10 μm, is drawn from the upper and lower surface of importation, output par, c be used as ternary system provided by the invention respectively The upper/lower electrode of relaxor ferroelectric monocrystal piezoelectric transformer.
Ternary system relaxation ferroelectric single crystal piezoelectric transformer polarised direction through-thickness provided by the invention, from upper surface to Lower surface, direction, importation all utilize the transversal stretching vibration mould of piezoelectric vibrator with output par, c as shown by the arrows in Figure 1 Formula, direction of vibration along its length, the transversal stretching pattern electromechanical coupling factor k of transformer31Up to more than 90%, d31It is reachable More than 1,500pC/N.
The piezoelectric element of ternary system relaxation ferroelectric single crystal piezoelectric transformer provided by the invention is ternary system relaxor ferroelectric list Brilliant material PMN-PIN-PT, concrete component 0.35PMN-0.32PIN-0.33PT, component are located at quasi- homotype phase boundary tripartite nearby Alpha region.
Ternary system relaxation ferroelectric single crystal piezoelectric transformer electric property
Impedance
Input and the impedance spectrum of output end are tested using electric impedance analyzer, the impedance spectrum point of input, output end Not as shown in Figure 2 and Figure 3, during the impedance spectrum of test input, will output terminal shortcircuit connection, will during the impedance spectrum of test output terminal Terminal shortcircuit connection is inputted, from Fig. 2, Fig. 3, in a short-circuit situation, transformer inputs, the resonant frequency of output end are about 35kHz。
Step-up ratio
Signal generator is connected to power amplifier, output signal is connected to input, output end and purely resistive are born Load is connected, and is commonly connected to oscillograph both ends, to test different loads and the step-up ratio under frequency, as a result as shown in Figure 4.By Fig. 4 understands that, with the increase of load, step-up ratio constantly increases, and resonant frequency moves to high frequency direction.
Power
Under matched load, the input of test transformer and the voltage of output end, electric current, transformation under respective load is calculated The actual power of device, so as to obtain the operating efficiency of transformer, transformer all has higher effect in wider frequency range Rate, it can reach more than 95%.
Fig. 5 is the relation curve of power output and input voltage, when input voltage is 250V, power output 2W.Surveying During examination, the temperature change of transformer is monitored using infrared radiation thermometer, it is defeated under conditions of transformer temperature rise is no more than 5 DEG C It is maximum up to 2.5W to go out power, corresponding power density is about 50W/cm3, significantly higher than the power density of ceramic transformer and The power density of binary PMN-PT monocrystalline transformers, wherein, the power density of conventional ceramic transformer is 7.7W/cm3, binary The power density of PMN-PT monocrystalline transformers is about 12W/cm3。
The specific embodiment of the present invention is described in detail above, but it is intended only as example, it is of the invention and unlimited It is formed on particular embodiments described above.To those skilled in the art, it is any to the equivalent modifications that carry out of the present invention and Substitute also all among scope of the invention.Therefore, the impartial conversion made without departing from the spirit and scope of the invention and Modification, all should be contained within the scope of the invention.

Claims (8)

  1. A kind of 1. ternary system relaxation ferroelectric single crystal piezoelectric transformer of transversal stretching vibration mode, it is characterised in that the monocrystalline Piezoelectric transformer includes piezoelectric element, and the material of the piezoelectric element is lead magnesio-niobate-lead niobate lead indate-lead-lead titanate monocrystal, described The chemical composition of lead magnesio-niobate-lead niobate lead indate-lead-lead titanates is (1-x-y) Pb (Mg1/3Nb2/3)O3-yPb(In1/2Nb1/2)O3- xPbTiO3, wherein, x=0.25-0.35, y=0.30-0.38；
    The transversal stretching pattern electromechanical coupling factor k of the monocrystalline piezoelectric transformer31More than 90%, d31More than 1,500pC/N.
  2. 2. ternary system relaxation ferroelectric single crystal piezoelectric transformer according to claim 1, it is characterised in that the magnoniobate Lead-lead niobate lead indate-lead-lead titanates is located at quasi- homotype phase boundary tripartite's alpha region nearby.
  3. 3. ternary system relaxation ferroelectric single crystal piezoelectric transformer according to claim 1, it is characterised in that the magnoniobate The crystallographic orientation of lead-lead niobate lead indate-lead-lead titanates be length along [100] direction, thickness is along [011] direction, width edgeSide To, and along thickness [011] direction polarization.
  4. 4. ternary system relaxation ferroelectric single crystal piezoelectric transformer according to claim 1, it is characterised in that the piezoelectric element Including upper and lower surface, the upper surface includes importation and output par, c, and it is defeated that the importation includes at least two Enter end, the output par, c includes at least one output end, and the output end is between the input；The following table bread Include common ground end.
  5. 5. ternary system relaxation ferroelectric single crystal piezoelectric transformer according to claim 4, it is characterised in that the piezoelectric element Size be：Length：Width >=5：1st, width：Thickness >=3：1.
  6. 6. ternary system relaxation ferroelectric single crystal piezoelectric transformer according to claim 4, it is characterised in that the input with 0.5-2mm is spaced between output end.
  7. 7. ternary system relaxation ferroelectric single crystal piezoelectric transformer according to claim 4, it is characterised in that the input, The Top electrode shape of output end is identical, equal sized.
  8. 8. ternary system relaxation ferroelectric single crystal piezoelectric transformer according to claim 4, it is characterised in that the monocrystalline piezoelectric For transformer under the conditions of temperature rise is less than 5 DEG C, power density is more than or equal to 50W/cm3。
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CN106500800A (en) * 2016-09-27 2017-03-15 华北电力大学 A kind of closed vessel liquid level measuring method based on supersonic guide-wave
CN106876574B (en) * 2017-03-03 2019-05-17 合肥工业大学 A kind of array piezoelectric transformer
CN108358634A (en) * 2018-01-19 2018-08-03 淮阴工学院 Textured piezoelectric ceramic material and preparation method thereof
CN109400153B (en) * 2018-10-11 2021-05-25 北京工业大学 Quaternary ceramic material with high transduction coefficient applied to piezoelectric energy collection and preparation
CN113964266B (en) * 2021-10-13 2023-09-19 中国科学院光电技术研究所 Method for preparing high-performance bismuth-based leadless piezoelectric driver

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